Route 3 in Trenton was shut down Wednesday afternoon, June 13, 2012, while firefighters tried to make sure an Island Explorer bus didn't explode after it was struck by a small pickup truck. Island Explorer buses are powered by propane gas, and this one was struck where its tank is located.

TRENTON, Maine — A small pickup truck struck the propane tank area of an Island Explorer bus late Wednesday afternoon on Route 3, causing police to halt traffic on the busy road, according to a Hancock County sheriff’s deputy.

The buses are powered by propane.

Traffic was not allowed on or off Mount Desert Island for several hours as firefighters tried to ensure the bus’ propane tank did not explode. Traffic was backed up for miles into the evening hours.